Ultima 1: The First Age of Darkness was one of the first open-world Computer Role Playing Games (CRPGs). Originally released in 1981 and remade for the PC in 1986, Ultima 1 was followed by a series of games that lasted almost 30 years, generated a cult following, inspired countless other RPGs, and pushed the boundaries of technology.

Ultima 1 is a fairly weird game, featuring an unusual combination of medieval fantasy and space travel. The world of Sosaria is being ravaged by the monsters of the evil wizard Mondain. Before you can face him in battle, you have to complete dungeoneering quests in the service of the lords of the land, become a space ace, free a princess, and travel back in time using a time machine.

The 1986 PC remake, on which the Ultima 1 Revenge project is based, is very old technology, by today’s standards. Still, it provides a vast array of learning areas. The game’s graphics are made up of three tilesets (CGA, EGA, and Tandy 1000), giving a choice for the differently powered machines of the time. The game world is stored in a small map file, where each four bits is an index into the tileset you’re using. Space travel is a combination of top-down 2D and first-person views. The dungeons are simple 3D-like line drawings, randomly generated based on a seed stored in the savegame file (so they remain consistent for each playthrough, but change if you start a new game). The different parts of the game run in different executables, and a special savegame file is used to pipe the player state from one to the other. Savegames mostly use 16-bit numbers, with the least significant byte stored first. Decoding the game files is an ongoing effort that powers tools such as the online map viewer I built in 2015, and the engine itself.

Today, I have released a demo of the engine. So if you own a copy of Ultima 1 (if you don’t, you can grab a copy from GOG), grab it from the downloads page, set the path to your original Ultima 1 folder in the settings file, and take a tour of Sosaria!